Electronic Components Datasheet Search
  English  ▼

Delete All


Preview PDF Download HTML

TPS254900A-Q1 Datasheet(PDF) 27 Page - Texas Instruments

Click here to check the latest version.
Part No. TPS254900A-Q1
Description  Automotive USB Host Charger With Short-to-VBATT Protection
Download  39 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  TI1 [Texas Instruments]
Direct Link  http://www.ti.com
Logo TI1 - Texas Instruments

TPS254900A-Q1 Datasheet(HTML) 27 Page - Texas Instruments

Back Button TPS254900A-Q1 Datasheet HTML 23Page - Texas Instruments TPS254900A-Q1 Datasheet HTML 24Page - Texas Instruments TPS254900A-Q1 Datasheet HTML 25Page - Texas Instruments TPS254900A-Q1 Datasheet HTML 26Page - Texas Instruments TPS254900A-Q1 Datasheet HTML 27Page - Texas Instruments TPS254900A-Q1 Datasheet HTML 28Page - Texas Instruments TPS254900A-Q1 Datasheet HTML 29Page - Texas Instruments TPS254900A-Q1 Datasheet HTML 30Page - Texas Instruments TPS254900A-Q1 Datasheet HTML 31Page - Texas Instruments Next Button
Zoom Inzoom in Zoom Outzoom out
 27 / 39 page
background image
Product Folder Links: TPS254900A-Q1
Submit Documentation Feedback
Copyright © 2017–2018, Texas Instruments Incorporated
Typical Application (continued)
9.2.1 Design Requirements
For this design example, use the following as the input parameters.
Battery voltage, V(BAT)
18 V
Short-circuit cable
0.5 m
9.2.2 Detailed Design Procedure
To begin the design process, the designer must know the following:
The battery voltage
The short-circuit cable length
The maximum continuous output current for the charging port. The minimum current-limit setting of
TPS254900A-Q1 device must be higher than this current.
The maximum output current of the upstream dc-dc converter. The maximum current-limit setting of
TPS254900A-Q1 device must be lower than this current.
For cable compensation, the total resistance including power switch rDS(on), cable resistance, and connector
contact resistance must be specified. Input Capacitance
Consider the following application situations when choosing the input capacitors.
For all applications, TI recommends a 0.1-µF or greater ceramic bypass capacitor between IN and GND, placed
as close as possible to the device for local noise decoupling.
During output short or hot plug-in of a capacitive load, high current flows through the TPS254900A-Q1 device
back to the upstream dc-dc converter until the TPS254900A-Q1 device responds (after t(IOS)). During this
response time, the TPS254900A-Q1 input capacitance and the dc-dc converter output capacitance source
current to keep VIN above the UVLO of the TPS254900A-Q1 device and any shared circuits. Size the input
capacitance for the expected transient conditions and keep the path between the TPS254900A-Q1 device and
the dc-dc converter short to help minimize voltage drops.
Input voltage overshoots can be caused by either of two effects. The first cause is an abrupt application of input
voltage in conjunction with input power-bus inductance and input capacitance when the IN pin is in the high-
impedance state (before turnon). Theoretically, the peak voltage is 2 times the applied voltage. The second
cause is due to the abrupt reduction of output short-circuit current when the TPS254900A-Q1 device turns off
and energy stored in the input inductance drives the input voltage high. Applications with large input inductance
(for example, a connection between the evaluation board and the bench power supply through long cables) may
require large input capacitance to prevent the voltage overshoot from exceeding the absolute-maximum voltage
of the device.
During the short-to-battery (EN = HIGH) condition, the input voltage follows the output voltage until OVP
protection is triggered (t(OV_OUT)). After the TPS254900A-Q1 device responds and turns off the power switch, the
stored energy in the input inductance can cause ringing.
Based on the three situations described, 10-µF and 0.1-µF low-ESR ceramic capacitors, placed close to the
input, are recommended. Output Capacitance
Consider the following application situations when choosing the output capacitors.
After an output short occurs, the TPS254900A-Q1 device abruptly reduces the OUT current, and the energy
stored in the output power-bus inductance causes voltage undershoot and potentially reverse voltage as it
Applications with large output inductance (such as from a cable) benefit from the use of a high-value output
capacitor to control the voltage undershoot.

Html Pages

1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32  33  34  35  36  37  38  39 

Datasheet Download

Go To PDF Page

Link URL

Privacy Policy
Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com

Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn